2.4gHz newbie :(

[Paul james 8]

Firstly, before I'm shot down in a hail of bullets I have tried to get my head around this before asking my specific question. The answers are no doubt out there but my single cell brain is struggling.

Having flown quite successfully using 35mHz radio I'm diving into the perils of 2.4gHz to hopefully allow me to use models with IC engines and sparky ignition things.

I have a DX8 TX and a couple of AR6200 RX to start with.

I want to put a receiver in a model with individual aileron control and both flaps working from the flap switch, flap servos connected to a "Y" harness.

Question is.....which RX channels should I use and how do I designate the flap switch to whichever channel is flaps? I guess flaps can only be either "gear" or "Aux1" ?

Doing this on my Futaba T9CHP was simple but not sure it will be so simple with the DX8

[John Lee]

There are several generations of the Dx8, but for the last few years the way is:

Hold down the roller when you switch on to enter the 'System Setup' Menu.

Scroll down to Aircraft Type, click.

Scroll to Wing:Normal, click, Rotate roller until you get to Wing: 2 Ail 1Flap click.

Click Back button (the lower of the 2 buttons to the left of the screen)

Scroll down to Channel Assign You will see that the Tx has assigned the Rx ports to AIL: Right Ail AUX1 Left Ail GEAR: Flap, these are all changeable if you wish, just click & scroll to change, but for the moment let's just leave them as the default.

Click Back button twice.

You should now be on the main (flying ) screen.

Click Roller to enter the Function List and scroll down to Flap System, click roller.

Scroll down to Inhibit. Click Roller. Rotate roller to select the switch you want to use for the flaps, or just toggle that switch & it will appear in the box by magic.

Click Roller & the menu expands enabling the Flap servo movement for each switch position to be set up with the corresponding elevator compensation if you need it. You can also change the switch for the flaps in this menu and the servo speed if you want a slow deployment or retraction.

When set up click the "Back' button to exit.

For me it's simpler than Futaba. The other things to note when changing from Futaba is that the throttle stick works the opposite way by default (So if you have reversed the throttle on your Futaba Tx on the Spectrum it needs to be Normal) & Expo is calibrated oppositely, so you will need positive expo on the Spektrum to soften the centre, not negative.

Edited By John Lee on 21/11/2018 15:47:08

[John Lee]

Another characteristic of Spektrum you may not be familiar with Paul is that the menu logic is such that options do not appear if they are not appropriate to that model type. e.g. you will not see the 'Flap System' menu if you have not told the Tx that the model has flaps in the Aircraft Type menu. You will not see the Crow Menu unless you have selected a 'Sailplane' Model Type etc.

It may save much grief to set up each model with a fresh memory & work your way logically down the 'System Setup' menu before trying to set up anything in the Function menu.

[Paul james 8]

Hi John,

That is exactly the sort of answer I needed so a big thank you for taking the time to explain it so clearly.

I will have a go at binding one of the receivers to the transmitter (or vice versa) and see if I can get it all to work.

I did hear that the methodology varies a bit from the Futaba system but I guess it will soon appear fairly logical.

[Paul james 8]

Having followed the very helpful instructions I got the binding done, connected it all up and its seems to be working Unfortunately one of the matched flap servos is faulty so I replaced that with a Futaba one but it doesn't seem to move at the same rate as the other one so I will put a second, matching Futaba in the other side and work out how to reverse it.

I pent a bit of time tinkering with settings, the menu seems fairly logical and the setting up went fine. I dialed in a bit of aileron expo and even adjusted the flap servo speed so they don't move at the speed of a top end rat trap.

If I had to find a weak point it is the roller jobbie; sometimes when rollering a fair few turns it is possible to inadvertently push it down and change what is being set. No big problem and I'm sure I will get used to it.

I'm now in search of some compatible 8 channel receivers so I can set up models with gear as well.

Thanks again for the info, it was invaluable!!.

[John Lee]

Glad it's worked Paul.

If you want to reverse one of the flap servos you can't of course use a Y lead unless you reverse it mechanically. If you select Wing:2Ail 2Flap you will need at least a 7 channel Rx (Motor, Run, Ele, 2 Ail, 2 Flap =7) and the Left Flap will be assigned to the Gear Channel & the Right Flap to Aux 2. You can then reverse one of the flap servos in Function List>Servo Setup.

An option for a 6 channel Rx is to use the Y lead on the ailerons & set the wing type to 1Ail 2 Flaps & then reassign the GEAR output to L Flap using the Rx Port Assignment screen.

Just be careful in your Rx search, there are plenty of dodgy cloned Spektrum Rx's about, I'd suggest you only use authorised outlets. Some of the bigger ones (eg Al, Sussex, TJD, Inwood) sometimes have bagged Rx's from when they split a Tx/Rx combo in the shop which can be picked up at a good price. Could be worth ringing around, they often don't appear on-line.

[Paul james 8]

Hi John,

All understood.

Don't really want to proiritise flap control over ailerons by giving each flap servo a separate channel so will tinker with a flap servo and see about altering the internal configuration.

Although we get around the direction of servo travel by using separate channels these days it would still be useful to be able to buy "handed" servos for jobs like this.

Thanks for the warning about dodgy receivers, I will be careful what I get.

[John Lee]

Posted by Paul james 8 on 22/11/2018 13:23:40:

Although we get around the direction of servo travel by using separate channels these days it would still be useful to be able to buy "handed" servos for jobs like this.

You must remember the days when we used to buy a reversed Futaba servo with a blue dot then! Perhaps you could just try applying some blue dots.........

[Paul james 8]

Any particular shade of blue??

[Former Member]

[This posting has been removed]

[Paul james 8]

Tried taking a 3003 apart but the motor and pot are soldered into the pcb

[Denis Watkins]

Do we not just put the pushrod on the other side of the servo arm, as we did pre computer radio.

[gangster]

Unless things have changed you can get handed servos. Futaba servos and Hitec servos rotate in opposite directions to each other

[Paul james 8]

Posted by Denis Watkins on 22/11/2018 21:43:44:

Do we not just put the pushrod on the other side of the servo arm, as we did pre computer radio.

In certain circumstances yes indeed, not unfortunately in the one I'm faced with here. I need matching servo travels from a "Y" lead or, I'm coming to think, a 7 channel receiver so I can have 4 channels dedicated to the flaps and ailerons.

[Paul james 8]

Given it some thought and think I will put both ailerons into the aileron channel using a "Y" lead than use the gear and aux1 for the flaps. I can get the up/down aileron differential by biasing the servo arms a little forward when the ailerons are level.

[Denis Watkins]

Posted by Paul james 8 on 22/11/2018 23:29:08:

Posted by Denis Watkins on 22/11/2018 21:43:44:

Do we not just put the pushrod on the other side of the servo arm, as we did pre computer radio.

In certain circumstances yes indeed, not unfortunately in the one I'm faced with here. I need matching servo travels from a "Y" lead or, I'm coming to think, a 7 channel receiver so I can have 4 channels dedicated to the flaps and ailerons.

Sorry to go on Paul, half of us use single servo Y lead aileron control, and with 4 channel, And precomputer radio we managed

The pushrods are adjustable, and can easily be set for equal travel

4 channels in the wing is great, but 4 servos too, where you already have what is needed

Your need can be accomplished with Y leads, and adjustable length aileron pushrods, and once that it is done, then that is the end of it once trimmed

[Nigel R]

"Don't really want to proiritise flap control over ailerons by giving each flap servo a separate channel so will tinker with a flap servo and see about altering the internal configuration."

Don't bother.

Buy a servo reverser widget from HobbkyKing.

https://hobbyking.com/en_us/turnigy-3-channel-servo-speed-direction-regulator.html

Will do flap speed control for all 3 outputs, one of which is reversed.

If you don't want speed control, a plain reverser:

https://hobbyking.com/en_us/turnigytm-servo-signal-reverser.html

[Paul james 8]

Posted by Denis Watkins on 23/11/2018 10:22:47:

Posted by Paul james 8 on 22/11/2018 23:29:08:

Posted by Denis Watkins on 22/11/2018 21:43:44:

Do we not just put the pushrod on the other side of the servo arm, as we did pre computer radio.

In certain circumstances yes indeed, not unfortunately in the one I'm faced with here. I need matching servo travels from a "Y" lead or, I'm coming to think, a 7 channel receiver so I can have 4 channels dedicated to the flaps and ailerons.

Sorry to go on Paul, half of us use single servo Y lead aileron control, and with 4 channel, And precomputer radio we managed

The pushrods are adjustable, and can easily be set for equal travel

4 channels in the wing is great, but 4 servos too, where you already have what is needed

Your need can be accomplished with Y leads, and adjustable length aileron pushrods, and once that it is done, then that is the end of it once trimmed

All understood but in this case it isn't quite that straightforward as I tried to explain above. I can't readily use a "Y" lead on the flaps due to on of the servos needing to be revered so the option is to use a servo reverser as mentioned by Nigel or to allocate two channels to the flaps to get one reversed.

As I can "Y" lead the ailerons without any trouble that is all feasible with the 6 channel rx.

[Paul james 8]

Posted by Nigel R on 23/11/2018 11:03:28:

"Don't really want to proiritise flap control over ailerons by giving each flap servo a separate channel so will tinker with a flap servo and see about altering the internal configuration."

Don't bother.

Buy a servo reverser widget from HobbkyKing.

https://hobbyking.com/en_us/turnigy-3-channel-servo-speed-direction-regulator.html

Will do flap speed control for all 3 outputs, one of which is reversed.

If you don't want speed control, a plain reverser:

https://hobbyking.com/en_us/turnigytm-servo-signal-reverser.html

I've seen these but never used them (as the need has not previously arisen) but have seen some comments suggesting they can be problematic. It is an option I will bear in mind for the future.